50 Philippine military officers and their supporters - including a former vice president - were accused of an attempt to trigger a "people power" revolt against the president.
The accused, most handcuffed to police escorts, were herded into a hall at police headquarters, where prosecutors read the complaints against them and presented evidence, including M16 assault rifles, ammunition, special armbands and two-way radios allegedly used in the failed uprising. The process continued until 1:30 a.m. Saturday.
President Gloria Macapagal Arroyo called the men desperate "lone wolves" who are blind to the people's wishes.
"Instead of striving under our democracy to unite the country, their actions only stoke selfish motives for self-interest," Arroyo said in a televised speech. "May the Filipino people take comfort in the fact that government institutions and civil society are strong and stable. The rule of law prevailed."
One of the accused, former Vice President Teofisto Guingona, was taken to a hospital due to an unspecified ailment. A Roman Catholic bishop was temporarily released to the custody of another bishop, prosecutor Emmanuel Velasco said.
About 3,000 left-wing activists earlier called for Arroyo's ouster over alleged corruption and human rights violations during two previously planned protests in Manila to honor a prominent Filipino revolutionary hero, police said.
They were blocked by police from approaching the presidential palace.
But those gatherings were tiny in comparison to the uprisings that ousted presidents in 2001 and 1986, and it appeared that Arroyo has survived yet another crisis.
The latest bid to oust her came Thursday, when 14 soldiers walked out of their trial on earlier insurrection charges and commandeered the five-star Peninsula Hotel.
They were led by Brig. Gen. Danilo Lim - suspected of involvement in another failed coup plot last year - along with Sen. Antonio Trillanes, a former navy officer who was elected to the Senate in May, and dozens of sympathizers within the military and leaders of leftist and opposition groups.
Lim issued a statement urging Arroyo to resign and asking the armed forces to withdraw support for her.
The events were remarkably similar to four years ago, when the same officers tried a similar tactic at another upscale hotel a few blocks away.
The result was nearly the same too, though Arroyo - clearly miffed that she continues to be dogged by attempts to oust her - showed less tolerance this time, dispatching troops and police SWAT teams. They fired tear gas and volleys of gunfire into the lobby of the Peninsula hotel and used an armored personnel carrier to bash in the roped-shut glass entrance doors.
Of the 101 people arrested at the hotel in Makati, Manila's business district, only 50 remained in custody Friday. They were all charged with rebellion, Velasco said.
National police chief Avelino Razon earlier said several documents were found at the hotel that "support the theory that this is a well-planned activity."
"There are other components ... and we are pursuing the other groups that might try to continue to implement their plans," Razon said.
The capital and surrounding areas were put under a one-night curfew to allow police to pursue follow-up arrests. Razon said authorities were still looking for some of the rebel soldiers who managed to escape, including one of the leaders, Capt. Nicanor Faeldon.
At least three previous coup plots and three impeachment attempts have plagued Arroyo's seven tumultuous years in power, but each has subsequently drawn fewer people to the streets.
Arroyo planned to go ahead with a previously scheduled trip to Spain and Britain on Saturday, presidential aide Cerge Remonde said.